1. Field of the Invention
Embodiments of the present invention relate to dishwashers, and more particularly to height adjustment mechanisms for a rack within a dishwasher and methods associated therewith.
2. Description of Related Art
A typical dishwasher includes a washtub that defines a front opening, which is sealed by a door pivoting about a substantially horizontal axis. Dishware to be washed may be positioned onto an upper rack or a lower rack. These racks move horizontally from a load position where at least a portion of the rack may be positioned outside of the washtub to facilitate loading or unloading of dishware, to a washing position wherein the racks are fully within the washtub. Movement of the lower rack is typically facilitated by rollers positioned on opposing sides of the rack that engage supporting surfaces on the washtub and/or the door, when the door is in an open position. The upper rack includes wheels or rollers that engage tracks slideably connected to opposing side walls of the washtub. The wheels or rollers slide or roll within the track, which itself slides in relation to the washtub, thereby allowing the upper rack to move horizontally between a load and a washing position.
One issue that may be encountered with conventional dishwashers is that the relative vertical positioning of the upper and lower racks is fixed. In some instances, an item needing to be washed may be too large to fit between the upper and lower racks. Alternatively, items needing to be positioned on the upper rack due to temperature or other concerns may be too large to fit between the upper rack and the upper surface of the washtub. Although some have attempted to address this issue by providing mechanisms for adjusting the height of the upper rack within the washtub, the mechanisms may be complicated and/or may require multiple operations to obtain an acceptable height of the rack. Furthermore, some prior art designs can be relatively unstable. Accordingly, an improved rack height adjustment mechanism would be desirable.